Coral reef ecosystems are under increasing pressure by multiple stressors that degrade reef condition and function. Although improved management systems have yielded benefits in many regions, broad‐scale declines continue and additional practical and effective solutions for reef conservation and management are urgently needed. Ecological interventions to assist or enhance ecosystem recovery are standard practice in many terrestrial management regimes, and they are now increasingly being implemented in the marine environment. Intervention activities in coral reef systems include the control of coral predators (e.g. crown‐of‐thorns starfish), substrate modification, the creation of artificial habitats and the cultivation, transplantation, and assisted recruitment of corals. On many coastal reefs, corals face competition and overgrowth by fleshy macroalgae whose abundance may be elevated due to acute disturbance events, chronic nutrient enrichment, and reduced herbivory. Active macroalgae removal has been proposed and trialed as a management tool to reduce competition between algae and corals and provide space for coral recruitment, in the hope of restoring the spatial dominance of habitat‐forming corals. However, macroalgae removal has received little formal attention as a method of reef restoration. This review synthesizes available knowledge of the ecological role of macroalgae on coral reefs and the potential benefits and risks associated with their active removal.

Cultivation of sponges is being explored to supply biomaterial for the pharmaceutical and cosmetics industries. This study assesses the impact of various cultivation methods on the microbial community within the sponge Rhopaloeides odorabile during: (1) in situ cultivation under natural environmental conditions, (2) ex situ cultivation in small flow-through aquaria and (3) ex situ cultivation in large mesocosm systems. Principal components analysis of denaturing gradient gel electrophoresis profiles indicated a stable microbial community in sponges cultured in situ (grown in the wild) and in sponges cultured ex situ in small flow-through aquaria over 12 weeks. In contrast, a shift in the microbial community was detected in sponges cultivated ex situ in large mesocosm aquaria for 12 months. This shift included (1) a loss of some stable microbial inhabitants, including members of the Poribacteria, Chloroflexi and Acidobacteria and (2) the addition of new microbes not detected in the wild sponges. Many of these acquired bacteria had highest similarity to known sponge-associated microbes, indicating that the sponge may be capable of actively selecting its microbial community. Alternatively, long-term ex situ cultivation may cause a shift in the dominant microbes that facilitates the growth of the more rare species. The microbial community composition varied between sponges cultivated in mesocosm aquaria with different nutrient concentrations and seawater chemistry, suggesting that these variables play a role in structuring the sponge-associated microbes. The high growth and symbiont stability in R. odorabile cultured in situ confirm that this is the preferred method of aquaculture for this species at this time.

Natural products (NPs) have historically been a fertile source of new drugs for the pharmaceutical industry. However, this once-popular approach has waned considerably over the past two decades as the high-throughput screening of megalibraries comprised mainly of molecules with non-natural (synthetic) motifs has unfolded. Contemporary high-throughput screening libraries contain molecules compliant with physicochemical profiles considered essential for downstream development. Until recently, there was no strategy that aligned NP screening with the same physicochemical profiles. An approach based on Log P has addressed these concerns and, together with advances in isolation, afforded NP leads in timelines compatible with pure compound screening. Concomitant progress related to access of biological resources has provided long-awaited legal certainty to further facilitate NP drug discovery.

Twenty-five years of Australian marine bioresources collecting and research by the Australian Institute of Marine Science (AIMS) has explored the breadth of latitudinally and longitudinally diverse marine habitats that comprise Australia’s ocean territory. The resulting AIMS Bioresources Library and associated relational database integrate biodiversity with bioactivity data, and these resources were mined to retrospectively assess biogeographic, taxonomic and phylogenetic patterns in cytotoxic, antimicrobial, and central nervous system (CNS)-protective bioactivity. While the bioassays used were originally chosen to be indicative of pharmaceutically relevant bioactivity, the results have qualified ecological relevance regarding secondary metabolism. In general, metazoan phyla along the deuterostome phylogenetic pathway (eg to Chordata) and their ancestors (eg Porifera and Cnidaria) had higher percentages of bioactive samples in the assays examined. While taxonomy at the phylum level and higher-order phylogeny groupings helped account for observed trends, taxonomy to genus did not resolve the trends any further. In addition, the results did not identify any biogeographic bioactivity hotspots that correlated with biodiversity hotspots. We conclude with a hypothesis that high-level phylogeny, and therefore the metabolic machinery available to an organism, is a major determinant of bioactivity, while habitat diversity and ecological circumstance are possible drivers in the activation of this machinery and bioactive secondary metabolism. This study supports the strategy of targeting phyla from the deuterostome lineage (including ancestral phyla) from biodiverse marine habitats and ecological niches, in future biodiscovery, at least that which is focused on vertebrate (including human) health.

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